FAA looks at redefining homebuilt 51-percent rule

July 21, 2008

The FAA is scrutinizing “fast build” homebuilt aircraft programs and with that may come policy changes that affect future kit designs.

The FAA has released several draft documents to clarify the regulation of the homebuilt aircraft segment. The biggest potential change is to the definition of the so-called 51-percent rule. The FAA’s original intention was that the individual would fabricate more than 50 percent and assemble more than 50 percent of the aircraft.

The FAA became concerned when fast-build kits entered the market where an aircraft owner’s contribution resulted in 51 percent of the assembly only. The agency felt that this did not meet the intent of building “solely for their own education or recreation.”

The FAA now defines 51 percent as the builder completing, at a minimum, 20 percent of the assembly and 20 percent of the fabrication with the remaining 11 percent made up from either additional assembly or fabrication. The FAA now states that the commercial assistance or “for hire” building programs will not count toward 20 percent of the assembly by the individual.

The policy changes would not affect those flying traditionally certified aircraft or already completed amateur-built aircraft. Existing kit designs essentially would be grandfathered, while new models, after the rules go into effect, would get the extra scrutiny.